Cisco Packet Tracer

https://www.packettracernetwork.com
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Cisco Packet Tracer is a powerful network simulator for CCNA and CCNP certification training that...
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### Arduino setup() Function in Packet Tracer and Arduino

Source: https://www.packettracernetwork.com/internet-of-things/pt7-arduino-programming

The setup() function is executed once when the program starts. In Packet Tracer, it's used for initial configurations like setting pin modes. The Arduino reference shows its use for initializing serial communication and pin modes.

```JavaScript
function setup() {
  pinMode(0, INPUT);
}
```

```C++
void setup()
{
  Serial.begin(9600);
  pinMode(buttonPin, INPUT);
}
```

--------------------------------

### Arduino Setup and Loop Functions in Packet Tracer

Source: https://www.packettracernetwork.com/internet-of-things

Demonstrates the implementation of `setup()` and `loop()` functions in Packet Tracer's Arduino environment. The `setup()` function initializes the program once, while `loop()` runs continuously to control the Arduino board.

```javascript
function setup() {
 pinMode(0, INPUT);
}

function loop() {
 Serial.println(digitalRead(0));
}
```

```c++
void setup()
{
 Serial.begin(9600);
 pinMode(buttonPin, INPUT);
}

void loop()
{
 if (digitalRead(buttonPin) == HIGH)
 Serial.write('H');
 else
 Serial.write('L');

 delay(1000);
}
```

--------------------------------

### Install Packet Tracer 7.0 (Linux)

Source: https://www.packettracernetwork.com/component/content/article/packettracer-7-newfeatures_Itemid=215&catid=18

This command executes the Packet Tracer installation script. It will prompt the user to accept the EULA and choose an installation directory (defaulting to /opt/pt). It may request root privileges via `sudo` to write to system directories and create a symbolic link in /usr/local/bin.

```bash
admin@ubuntu01:~/PacketTracer70$ ./install

Welcome to Cisco Packet Tracer 7.0 Installation

Read the following End User License Agreement “EULA” carefully. You must accept the terms of this EULA to install and use Cisco Packet Tracer.

Press the Enter key to read the EULA.  Press the EnterCisco Packet Tracer Software License AgreementIMPORTANT: PLEASE READ THIS CISCO PACKET TRACER SOFTWARE LICENSE AGREEMENT (THE "AGREEMENT") CAREFULLY. DOWNLOADING, INSTALLING OR USING THE CISCO PACKET TRACER SOFTWARE CONSTITUTES ACCEPTANCE OF THIS AGREEMENT. IF YOU DO NOT AGREE ........................ .......................... Cisco, Cisco Systems, and the Cisco Systems logo are registered trademarks of Cisco Systems, Inc. in the U.S. and certain other countries. Any other trademarks mentioned in this document are the property of their respective owners.Do you accept the terms of the EULA? (Y)es/(N)o Y
You have accepted the terms to the EULA. Congratulations. Packet Tracer will now be installed.
Enter location to install Cisco Packet Tracer or press enter for default [/opt/pt]:
Installing into /opt/pt

Not able to create and copy files to /opt/pt
Should we try to gain root access with sudo? [Yn] Y
[sudo] password for admin:
Installing into /opt/pt
Copied all files successfully to /opt/pt

Should we create a symbolic link “packettracer” in /usr/local/bin for easy Cisco Packet Tracer startup? [Yn] Y
Type “packettracer” in a terminal to start Cisco Packet Tracer
Writing PT7HOME environment variable to /etc/profile

Cisco Packet Tracer 7.0 installed successfully
admin@ubuntu01:~/PacketTracer70$
```

--------------------------------

### Start Real HTTP Server in Javascript

Source: https://www.packettracernetwork.com/internet-of-things/pt7-iot-real-http-server

This snippet demonstrates how to initialize and start a real HTTP server on a specified TCP port using Javascript within Packet Tracer. It utilizes the `RealHTTPServer` class and its `start` method.

```javascript
var server = new RealHTTPServer();
server.start(8080);
```

--------------------------------

### Start Real HTTP Server in Python

Source: https://www.packettracernetwork.com/internet-of-things/pt7-iot-real-http-server

This Python code demonstrates how to start a real HTTP server on a given port. It requires importing the `realhttp` package and using the `HTTPServer.start` method. The function returns a boolean indicating success.

```python
from realhttp import *

# ... (route definitions)

HTTPServer.start(80)
```

--------------------------------

### Install Cisco Packet Tracer on Ubuntu 22.04 (CLI)

Source: https://www.packettracernetwork.com/features/packettracer-82-newfeatures

This command initiates the installation of Cisco Packet Tracer 8.2.2 on Ubuntu 22.04. It requires elevated privileges and may encounter dependency issues with 'libgl1-mesa-glx'.

```bash
# apt-get install CiscoPacketTracer822_amd64_signed.deb
(Reading database ... 218755 files and directories currently installed.)
Preparing to unpack CiscoPacketTracer.deb ...
Unpacking packettracer (8.2.2) over (8.2.2) ...
gtk-update-icon-cache: No theme index file.
dpkg: dependency problems prevent configuration of packettracer:
 packettracer depends on libgl1-mesa-glx; however:
  Package libgl1-mesa-glx is not installed.

dpkg: error processing package packettracer (--install):
 dependency problems - leaving unconfigured
Processing triggers for shared-mime-info (2.4-4) ...
Errors were encountered while processing:
 packettracer

```

--------------------------------

### Install GNS3 GUI on Debian/Ubuntu

Source: https://www.packettracernetwork.com/features/packet-tracer-vs-gns3

This snippet shows the commands to add the GNS3 PPA repository and install the GNS3 GUI on Debian or Ubuntu-based Linux distributions. This is a prerequisite for using GNS3 on these systems.

```bash
sudo add-apt-repository ppa:gns3/ppa-v3
sudo apt install gns3-gui
```

--------------------------------

### Manually Install libgl1-mesa-glx on Ubuntu 22.04 (CLI)

Source: https://www.packettracernetwork.com/features/packettracer-82-newfeatures

This sequence of commands provides a workaround for installing the 'libgl1-mesa-glx' dependency on Ubuntu 22.04, which is required for Cisco Packet Tracer 8.2.2. It involves installing base packages, downloading the specific .deb file, and then installing it.

```bash
1. sudo apt install libgl1 libglx-mesa0
2. wget http://mirrors.kernel.org/ubuntu/pool/universe/m/mesa/libgl1-mesa-glx_22.0.1-1ubuntu2_amd64.deb
3. sudo apt install ./libgl1-mesa-glx_22.0.1-1ubuntu2_amd64.deb

Then, resume Cisco Packet Tracer 8.2.2 install with **sudo apt-get install CiscoPacketTracer822_amd64_signed.deb**
```

--------------------------------

### Navigate to Packet Tracer Directory (Linux)

Source: https://www.packettracernetwork.com/component/content/article/packettracer-7-newfeatures_Itemid=215&catid=18

This command changes the current directory to the 'PacketTracer70' folder, which is created after extracting the archive. This is a necessary step before running the installation script.

```bash
cd PacketTracer70/
```

--------------------------------

### Example VLAN Pruning Configuration

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccnp-switch

This example demonstrates configuring a FastEthernet interface as a trunk and then manually pruning allowed VLANs. This limits the VLANs that can pass through the trunk link.

```cisco
Switch(config)#interface fastEthernet 0/1
Switch(config-if)#switchport mode trunk
Switch(config-if)#switchport trunk allowed vlan 10,11,12
```

--------------------------------

### Cisco Packet Tracer BGP Configuration Example

Source: https://www.packettracernetwork.com/features/packet-tracer-vs-gns3

This example demonstrates a basic BGP configuration within Cisco Packet Tracer's simulated IOS environment. It shows how to enter BGP configuration mode and lists available BGP commands, focusing on features relevant for CCNA and CCNP certification preparation.

```cisco-ios
Router(config)#router bgp 65000
Router(config-router)#%BGP-4-NORTRID: BGP could not pick a router-id. Please configure manually.

Router(config-router)#?
  bgp              BGP specific commands
  distance         Define an administrative distance
  exit             Exit from routing protocol configuration mode
  neighbor         Specify a neighbor router
  network          Specify a network to announce via BGP
  no               Negate a command or set its defaults
  redistribute     Redistribute information from another routing protocol
  synchronization  Perform IGP synchronization
  timers           Adjust routing timers
```

--------------------------------

### MQTT Message Examples in Packet Tracer

Source: https://www.packettracernetwork.com/internet-of-things/mqtt-protocol

This snippet displays example MQTT messages used for communication between IoT devices in Cisco Packet Tracer. These messages demonstrate various commands like ID, CONNECT, CONNACK, SUBSCRIBE, SUBACK, and PUBLISH, showcasing the protocol's structure and data exchange.

```json
{"cmd":"ID","ID":"357fa587ed1de0L"}
{"cmd":"CONNECT","client": "MQTT Client (357fa587ed1de0L)","protocolId":"MQTT","protocolVersion":"3.1.1", "clean":1, "clientId":"357fa587ed1de0L", "keepalive":60, "username":"cisco", "password":"cisco", "will":{}}
{"cmd":"CONNACK","client":"MQTT Client (357fa587ed1de0L)","returnCode":0,"sessionPresent":0}
{"cmd":"SUBSCRIBE","client":"MQTT Client (357fa587ed1de0L)","packetId":31276,"topic":"myhome/bedroom/temp","qos":0}
{"cmd":"SUBACK","client":"MQTT Client (357fa587ed1de0L)","packetId":31276,"topic":"myhome/bedroom/temp","qos":0,"returnCode":0}
{"cmd":"SUBSCRIBE","client":"MQTT Client (357fa587ed1de0L)","packetId":23347,"topic":"myhome","qos":0}
{"cmd":"SUBACK","client":"MQTT Client (357fa587ed1de0L)","packetId":23347,"topic":"myhome","qos":0,"returnCode":0}
{"cmd":"PUBLISH","client":"MQTT Client (357fa587ed1de0L)","qos":0,"dup":0,"topic":"myhome/bedroom/temp","payload":"TestTestTest","retain":0}
{"cmd":"PUBLISH","client":"MQTT Client (357fa587ed1de0L)","qos":0,"dup":0,"topic":"myhome/bedroom/temp","payload":"TestTestTest","retain":0}
```

--------------------------------

### Get SDN Controller Security Token and List Network Devices (Python)

Source: https://www.packettracernetwork.com/features/packettracer-80-newfeatures

This Python script demonstrates how to interact with the Cisco Packet Tracer 8.0 SDN controller's REST API. It first retrieves a security token using POST request and then uses this token to fetch a list of network devices via a GET request. Note that the Python code emulated in Packet Tracer may differ from standard Python environments.

```python
import json
import requests

def main():
	
	#Get security token
	securityUrl = "http://localhost:58000/api/v1/ticket"
	securityData = json.dumps({"username": "test","password": "test"})
	securityHeader = {'Content-type': 'application/json'}
	r = requests.post(securityUrl, data=securityData, headers=securityHeader)
	token = r.json()["response"]["serviceTicket"]
	print("token: " + token)

	#Get hosts
	apiAccessHeader = {}
	apiAccessHeader['content-type'] = 'application/json'
	apiAccessHeader['x-auth-token'] = token
	r = requests.get('http://localhost:58000/api/v1/network-device', headers=apiAccessHeader);
	print(json.dumps(r.json(), indent=2))

if __name__ == "__main__":
	main()

```

--------------------------------

### Get Security Token and List Network Devices

Source: https://www.packettracernetwork.com/features/packettracer-80-newfeatures

This endpoint retrieves a security token required for subsequent API calls and then lists all network devices managed by the SDN controller.

```APIDOC
## POST /api/v1/ticket and GET /api/v1/network-device

### Description
This API allows you to obtain a security token by providing username and password, which is then used to authenticate requests for listing network devices. The response includes details about each device such as platform type, serial number, IOS version, interface count, IP addresses, and uptime.

### Method
POST (for token), GET (for devices)

### Endpoint
- Token: `http://localhost:58000/api/v1/ticket`
- Devices: `http://localhost:58000/api/v1/network-device`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body (for POST /api/v1/ticket)
- **username** (string) - Required - The username for authentication.
- **password** (string) - Required - The password for authentication.

### Request Example (POST /api/v1/ticket)
```json
{
    "username": "test",
    "password": "test"
}
```

### Request Example (GET /api/v1/network-device)
Headers:
- `Content-type`: `application/json`
- `x-auth-token`: `[Retrieved Security Token]`

### Response
#### Success Response (200) for GET /api/v1/network-device
- **response** (array) - A list of network devices.
  - **platformId** (string) - The platform type of the device (e.g., "ISR4300").
  - **serialNumber** (string) - The serial number of the device.
  - **softwareVersion** (string) - The IOS software version running on the device.
  - **interfaceCount** (string) - The number of interfaces on the device.
  - **macAddress** (string) - The MAC address of the device.
  - **ipAddresses** (array of strings) - A list of IP addresses assigned to the device.
  - **upTime** (string) - The uptime of the device.
  - ... (other device-specific details)

#### Response Example (GET /api/v1/network-device)
```json
{
  "response": [
    {
      "collectionStatus": "Managed",
      "connectedInterfaceName": [
        "FastEthernet0/3",
        "GigabitEthernet0/0/0"
      ],
      "connectedNetworkDeviceIpAddress": [
        "",
        "2.1.1.2"
      ],
      "connectedNetworkDeviceName": [
        "Switch",
        "Router"
      ],
      "errorDescription": "",
      "globalCredentialId": "ca8f6f2a-eef2-488e-96da-96c42eb80548",
      "hostname": "Router",
      "id": "FDO13025YJT-uuid",
      "interfaceCount": "4",
      "inventoryStatusDetail": "Managed",
      "ipAddresses": [
        "1.1.1.5",
        "2.1.1.1"
      ],
      "lastUpdateTime": "31",
      "lastUpdated": "2020-02-14 20:18:51",
      "macAddress": "000C.85AD.AB89",
      "managementIpAddress": "1.1.1.5",
      "platformId": "ISR4300",
      "productId": "ISR4331",
      "reachabilityFailureReason": "",
      "reachabilityStatus": "Reachable",
      "serialNumber": "FDO13025YJT-",
      "softwareVersion": "15.4",
      "type": "Router",
      "upTime": "18 minutes, 58 seconds"
    }
  ]
}
```
```

--------------------------------

### Configure Console Access Security in Cisco IOS

Source: https://www.packettracernetwork.com/labs/lab6-basicroutersetup

This set of commands configures the console line for secure access, including setting a password, enabling login, setting command history size, and configuring an executive timeout.

```cisco
GATEWAY(config)#line console 0
GATEWAY(config-line)#password cisco
GATEWAY(config-line)#login
GATEWAY(config-line)#logging synchronous 
GATEWAY(config-line)#exec-timeout 2 45
GATEWAY(config-line)#history size 10
```

--------------------------------

### Configure 802.1x Authentication

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccnp-switch

This example configures wired 802.1x authentication on a Catalyst switch using IOS 15. It involves enabling AAA, defining dot1x authentication lists, and configuring interfaces for authentication.

```cisco
aaa new-model
aaa authentication dot1x default group radius
dot1x system-auth-control
!
interface Vlan10
 mac-address 000c.cfb1.ce02
 ip address 192.168.10.1 255.255.255.0
!
radius-server host 192.168.10.3 auth-port 1645 key radius
!
interface FastEthernet0/1
 switchport mode access
 switchport nonegotiate
 no cdp enable
 authentication port-control auto
 dot1x pae authenticator
!
```

--------------------------------

### Arduino loop() Function in Packet Tracer and Arduino

Source: https://www.packettracernetwork.com/internet-of-things/pt7-arduino-programming

The loop() function runs continuously after setup(). Packet Tracer's implementation reads digital input and prints it, while Arduino's example reads a button state and controls an LED, demonstrating continuous operation.

```JavaScript
function loop() {
  Serial.println(digitalRead(0));
}
```

```C++
void loop()
{
  if (digitalRead(buttonPin) == HIGH)
    Serial.write('H');
  else
    Serial.write('L');

  delay(1000);
}
```

--------------------------------

### Display OSPF Interface Brief Status (Packet Tracer)

Source: https://www.packettracernetwork.com/features/packettracer-82-newfeatures

This command displays a summary of OSPF interfaces, their process IDs, areas, IP addresses, costs, states, and neighbor counts. It is useful for verifying OSPF configuration and adjacency status on network devices.

```network-cli
Router#show ip ospf interface brief 
Interface     PID   Area                     IP Address/Mask          Cost  State  Nbrs F/C
Se0/0/0         1   0.0.0.0                       10.0.0.1/255.0.0.0   64   POINT  0/0
Fa0/1           1   0.0.0.0                       11.0.0.1/255.0.0.0   1     WAIT  0/0


```

```network-cli
Router#show ip ospf interface brief 
Interface     PID   Area                     IP Address/Mask          Cost  State  Nbrs F/C
Se0/0/0         1   0.0.0.0                       10.0.0.1/255.0.0.0   64   POINT  0/0
Fa0/1           1   0.0.0.0                       11.0.0.1/255.0.0.0   1      BDR  0/0


```

--------------------------------

### Configure HTTP Routes in Javascript

Source: https://www.packettracernetwork.com/internet-of-things/pt7-iot-real-http-server

This example shows how to define routes for an HTTP server in Javascript using the `HTTPServer.route` method. It includes setting up a specific path '/hello' to respond with 'world' and a wildcard route '/*' to respond with 'hi'. The `response.send` method is used to send back the content.

```javascript
HTTPServer.route("/hello", function(url, response) {  response.send("world"); });  

HTTPServer.route("/*", function(url, response) {  response.send("hi"); });
```

--------------------------------

### Arduino pinMode() Function in Packet Tracer and Arduino

Source: https://www.packettracernetwork.com/internet-of-things/pt7-arduino-programming

The pinMode() function configures a digital pin as either an input or an output. Examples show setting pin 1 to OUTPUT and pin 2 to INPUT in Packet Tracer, and configuring an LED pin as output in Arduino's setup.

```JavaScript
pinMode(1, OUTPUT);
pinMode(2, INPUT);
```

```C++
void setup()
{
  pinMode(ledPin, OUTPUT);      // sets the digital pin as output
}

void loop()
{
  digitalWrite(ledPin, HIGH);   // sets the LED on
  delay(1000);                  // waits for a second
  digitalWrite(ledPin, LOW);    // sets the LED off
  delay(1000);                  // waits for a second
}
```

--------------------------------

### Configure HTTP Routes in Python

Source: https://www.packettracernetwork.com/internet-of-things/pt7-iot-real-http-server

This Python snippet illustrates setting up routes for an HTTP server using the `HTTPServer.route` function. It shows how to associate specific URL paths and HTTP methods (like GET or POST) with callback functions. Wildcards are supported using '*'.

```python
def onRouteHello(url, response):
  response.send("hello")
HTTPServer.route("/hello", onRouteHello)

def onRouteAll(url, response):
  response.send("world")HTTPServer.route("/*", onRouteAll)

server.route("/contacts/*", ["GET"], get_contacts)
server.route("/services/*", ["GET"], get_services)
server.route("/data/*", ["POST"], post_data)
```

--------------------------------

### Verify PPP Encapsulation with 'show interfaces'

Source: https://www.packettracernetwork.com/labs

Verifies that PPP encapsulation is correctly configured and enabled on a serial interface. It also displays other interface parameters like IP address, MTU, and keepalive status.

```network-cli
Router-B#show interfaces serial 0/0/0
Serial0/0/0 is up, line protocol is up (connected)
  Hardware is HD64570
  Internet address is 192.168.10.5/30
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation PPP, loopback not set, keepalive set (10 sec)
  Last input never, output never, output hang never
  [...]
```

--------------------------------

### Install Packet Tracer 7.3 on Ubuntu

Source: https://www.packettracernetwork.com/features/packettracer-73-newfeatures

This command installs the Cisco Packet Tracer 7.3 .deb package on Ubuntu 18.04.3 LTS. It uses the dpkg command, which is the standard package manager for Debian-based systems like Ubuntu.

```bash
sudo dpkg -i PacketTracer_730_amd64.deb
```

--------------------------------

### Configure and Verify STP Protocols (PVST+, Rapid-PVST+)

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccna

This snippet illustrates configuring and verifying Spanning Tree Protocol (STP) modes, specifically PVST+ and Rapid-PVST+, on Packet Tracer emulated switches. It shows how to set the STP mode and configure the root bridge manually or automatically. MSTP is not supported.

```cisco-ios
Switch(config)#spanning-tree mode ?
  pvst        Per-Vlan spanning tree mode
  rapid-pvst  Per-Vlan rapid spanning tree mode

Switch(config)#spanning-tree vlan 1 priority 
% Bridge Priority must be in increments of 4096.
% Allowed values are:
  0     4096  8192  12288 16384 20480 24576 28672
  32768 36864 40960 45056 49152 53248 57344 61440

Switch(config)#spanning-tree vlan 100 root primary 
```

--------------------------------

### Configure OSPF Routing in Cisco Packet Tracer

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccnp-enterprise

This snippet demonstrates the initial configuration of the OSPF routing process in Cisco Packet Tracer. It includes commands for setting up OSPF areas, configuring interface costs, managing default information, and defining neighbors. Support for various OSPF area types like backbone, standard, stub, and NSSA is highlighted.

```cisco
Router(config)#router ospf 20
Router(config-router)#?
  area                   OSPF area parameters
  auto-cost              Calculate OSPF interface cost according to bandwidth
  default-information    Control distribution of default information
  distance               Define an administrative distance
  exit                   Exit from routing protocol configuration mode
  log-adjacency-changes  Log changes in adjacency state
  neighbor               Specify a neighbor router
  network                Enable routing on an IP network
  no                     Negate a command or set its defaults
  passive-interface      Suppress routing updates on an interface
  redistribute           Redistribute information from another routing protocol
  router-id              router-id for this OSPF process

Router(config-router)#area 10 ?
  authentication  Enable authentication
  default-cost    Set the summary default-cost of a NSSA/stub area
  nssa            Specify a NSSA area
  range           Summarize routes matching address/mask (border routers only)
  stub            Specify a stub area
  virtual-link    Define a virtual link and its parameters

```

--------------------------------

### Install and Uninstall VM on ISR 819 Router

Source: https://www.packettracernetwork.com/internet-of-things/iot-with-iox

These commands show how to install and uninstall a virtual machine (VM) package from the router's flash memory. Only one of these commands should be executed at a time.

```cisco
Router#virtual-service install name vm1 package flash:/vm1.ova

Router#virtual-service uninstall name vm1
```

--------------------------------

### Configure Standard and Extended Access Lists on Cisco Switches

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccna

This section shows the initial configuration steps for creating standard and extended IP access lists on Cisco switches. It covers defining the access list number and specifying whether to permit or deny traffic, along with adding remarks.

```cisco
Switch(config)#access-list ?
  <1-99>     IP standard access list
  <100-199>  IP extended access list

Switch(config)#access-list 100 ?
  deny    Specify packets to reject
  permit  Specify packets to forward
  remark  Access list entry comment
```

--------------------------------

### Arduino digitalWrite() Function in Packet Tracer and Arduino

Source: https://www.packettracernetwork.com/internet-of-things/pt7-arduino-programming

The digitalWrite() function writes a HIGH or LOW value to a digital pin. Packet Tracer's example sets pin 1 to HIGH, while Arduino's example demonstrates turning an LED on and off repeatedly with delays.

```JavaScript
digitalWrite(1, HIGH);
```

```C++
void loop()
{
  digitalWrite(ledPin, HIGH);   // sets the LED on
  delay(1000);                  // waits for a second
  digitalWrite(ledPin, LOW);    // sets the LED off
  delay(1000);                  // waits for a second
}
```

--------------------------------

### Arduino digitalRead() Function in Packet Tracer and Arduino

Source: https://www.packettracernetwork.com/internet-of-things/pt7-arduino-programming

The digitalRead() function reads the value from a specified digital pin, returning HIGH or LOW. Packet Tracer's example assigns the read value to a variable, while Arduino's example uses it to control an LED based on button input.

```JavaScript
var val = digitalRead(1);
```

```C++
void loop()
{
  val = digitalRead(inPin);   // read the input pin
  digitalWrite(ledPin, val);    // sets the LED to the button's value
}
```

--------------------------------

### Troubleshoot EtherChannel Switchport Configuration

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccnp-enterprise

This snippet demonstrates how to use the 'show interfaces <interface name> switchport' command to troubleshoot EtherChannels. It helps detect mismatches in native VLAN or trunk encapsulation between switches, essential for static and dynamic EtherChannels.

```cisco-ios
Switch#show interfaces fastEthernet 0/1 switchport 
Name: Fa0/1
Switchport: Enabled
Administrative Mode: dynamic desirable
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: All
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Unknown unicast blocked: disabled
Appliance trust: none
```

--------------------------------

### GNS3 BGP Configuration Example

Source: https://www.packettracernetwork.com/features/packet-tracer-vs-gns3

This snippet demonstrates basic Border Gateway Protocol (BGP) configuration commands within GNS3, simulating a Cisco ISR router. It shows how to enter BGP configuration mode and lists available commands for managing BGP settings, such as neighbor configuration and network advertisement.

```cisco-ios-config
R2(config)#router bgp 50000
R2(config-router)#?
Router configuration commands:
  address-family       Enter Address Family command mode
  aggregate-address    Configure BGP aggregate entries
  auto-summary         Enable automatic network number summarization
  bgp                  BGP specific commands
  default              Set a command to its defaults
  default-information  Control distribution of default information
  default-metric       Set metric of redistributed routes
  distance             Define an administrative distance
  distribute-list      Filter networks in routing updates
  exit                 Exit from routing protocol configuration mode
  help                 Description of the interactive help system
  maximum-paths        Forward packets over multiple paths
  neighbor             Specify a neighbor router
  network              Specify a network to announce via BGP
  no                   Negate a command or set its defaults
  redistribute         Redistribute information from another routing protocol
  synchronization      Perform IGP synchronization
  table-map            Map external entry attributes into routing table
  template             Enter template command mode
  timers               Adjust routing timers

```

--------------------------------

### Configure and Verify Interswitch Connectivity (Trunking, VTP, 802.1Q)

Source: https://www.packettracernetwork.com/ccna-ccnp-preparation/ccna

This snippet shows how to configure and verify interswitch connectivity using trunk ports, VTP (versions 1 & 2), and 802.1Q on Packet Tracer emulated switches. It covers trunk port modes, VLAN allowed on trunk, DTP, VTP configuration, and native VLAN settings. DTP can be disabled using 'switchport nonegotiate'.

```cisco-ios
Switch(config)#vtp ?
  domain    Set the name of the VTP administrative domain.
  mode      Configure VTP device mode
  password  Set the password for the VTP administrative domain
  version   Set the adminstrative domain to VTP version

Switch(config)#vtp version ?
  <1-2>  Set the adminstrative domain VTP version number

Switch(config)#vtp mode ?
  client       Set the device to client mode.
  server       Set the device to server mode.
  transparent  Set the device to transparent mode.

Switch(config-if)#switchport trunk native ?
  vlan  Set native VLAN when interface is in trunking mode
```

--------------------------------

### Verify IPSEC Tunnel Establishment using Cisco ASA Show Commands

Source: https://www.packettracernetwork.com/labs/lab17-asa-ipsec-vpn

These commands are used on Cisco ASA firewalls to check the status of IPSEC VPN tunnels. 'show crypto isakmp sa' displays the status of IKE Security Associations, indicating if the initial key exchange has been successful. 'show crypto ipsec sa' provides details on the IPSEC Security Associations, including packet counters for encrypted and decrypted traffic, SPIs, and SA lifetime.

```network-cli
ASA-CAMPUS-VPN#show crypto isakmp sa 

IKEv1 SAs:

  Active SA: 1
  Rekey SA: 0 (A tunnel will report 1 Active and 1 Rekey SA during rekey)

Total IKE SA: 1
1   IKE Peer: 134.95.56.18
    Type    : L2L             Role    : Initiator
    Rekey   : no              State   : QM_IDLE

There are no IKEv2 SAs

 

ASA-CAMPUS-VPN#show crypto ipsec sa 

interface: outside
    Crypto map tag: BRANCH1, seq num: 1, local addr 134.95.56.17

      permit tcp object CAMPUS_NETWORK object BRANCH01_NETWORK
      local  ident (addr/mask/prot/port): (172.16.0.0/255.255.128.0/6/0)
      remote  ident (addr/mask/prot/port): (172.16.129.0/255.255.255.0/6/0)
      current_peer 134.95.56.18
      #pkts encaps: 0, #pkts encrypt: 0, #pkts digest: 0
      #pkts decaps: 6, #pkts decrypt: 6, #pkts verify: 0
      #pkts compressed: 0, #pkts decompressed: 0
      #pkts not compressed: 0, #pkts comp failed: 0, #pkts decomp failed: 0
      #pre-frag successes: 0, #pre-frag failures: 0, #fragments created: 0
      #PMTUs sent: 0, #PMTUs rcvd: 0, #decapsulated frgs needing reassembly: 0
      #send errors 0, #recv errors 0

      local crypto endpt.: 134.95.56.17/0, remote crypto endpt.:134.95.56.18/0
      path mtu 1500, ip mtu, ipsec overhead 78,  media mtu 1500
      current outbound spi: 0x6386132D(1669731117)
      current inbound spi: 0x04B729EA(1669731117)

     inbound esp sas:
      spi: 0x04B729EA(79112682)
         transform: esp-aes 256 esp-sha-hmac no compression
         in use settings ={L2L, Tunnel, }
         slot: 0, conn id: 2007, crypto map: BRANCH1
         sa timing: remaining key lifetime (k/sec): (4525504/85906)
         IV size: 16 bytes
         replay detection support: N
         Anti replay bitmap:
          0x00000000 0x0000001F
     outbound esp sas:
      spi: 0x6386132D(1669731117)
         transform: esp-aes 256 esp-sha-hmac no compression
         in use settings ={L2L, Tunnel, }
         slot: 0, conn id: 2008, crypto map: BRANCH1
         sa timing: remaining key lifetime (k/sec): (4525504/85906)
         IV size: 16 bytes
         replay detection support: N
         Anti replay bitmap:
          0x00000000 0x00000001

    Crypto map tag: BRANCH1, seq num: 1, local addr 134.95.56.17

      permit icmp object CAMPUS_NETWORK object BRANCH01_NETWORK
      local  ident (addr/mask/prot/port): (172.16.0.0/255.255.128.0/1/0)
      remote  ident (addr/mask/prot/port): (172.16.129.0/255.255.255.0/1/0)
      current_peer 134.95.56.18
      #pkts encaps: 7, #pkts encrypt: 7, #pkts digest: 0
      #pkts decaps: 0, #pkts decrypt: 0, #pkts verify: 0
      #pkts compressed: 0, #pkts decompressed: 0
      #pkts not compressed: 0, #pkts comp failed: 0, #pkts decomp failed: 0
      #pre-frag successes: 0, #pre-frag failures: 0, #fragments created: 0
      #PMTUs sent: 0, #PMTUs rcvd: 0, #decapsulated frgs needing reassembly: 0
      #send errors 1, #recv errors 0

      local crypto endpt.: 134.95.56.17/0, remote crypto endpt.:134.95.56.18/0
      path mtu 1500, ip mtu, ipsec overhead 78,  media mtu 1500
      current outbound spi: 0x6386132D(1669731117)
      current inbound spi: 0x04B729EA(1669731117)

     inbound esp sas:
      spi: 0x04B729EA(79112682)
         transform: esp-aes 256 esp-sha-hmac no compression
         in use settings ={L2L, Tunnel, }
         slot: 0, conn id: 2007, crypto map: BRANCH1
         sa timing: remaining key lifetime (k/sec): (4525504/85906)
         IV size: 16 bytes
         replay detection support: N
         Anti replay bitmap:
          0x00000000 0x0000001F
     outbound esp sas:
      spi: 0x6386132D(1669731117)
         transform: esp-aes 256 esp-sha-hmac no compression
         in use settings ={L2L, Tunnel, }
         slot: 0, conn id: 2008, crypto map: BRANCH1
         sa timing: remaining key lifetime (k/sec): (4525504/85906)
         IV size: 16 bytes
         replay detection support: N
         Anti replay bitmap:
          0x00000000 0x00000001
```

--------------------------------

### Enable Password Encryption in Cisco IOS

Source: https://www.packettracernetwork.com/labs/lab6-basicroutersetup

This command enables the encryption of all plaintext passwords stored in the router's configuration, enhancing security.

```cisco
GATEWAY(config)#service password-encryption
```
Tokens:
Raw